| No | Pattern | Freq | Relations |
|---|---|---|---|
| 1 | must have been [adv] a [noun sg] | 18 |
|
| 2 | must have been [adv] a [noun sg] | 17 |
|
| 3 | must have been quite a [noun sg] | 11 |
|
| 4 | must have been quite a [noun sg] | 11 |
|
